SystemUI : Clock position support + am/pm styles

Based on Dave Kessler's work from cm-12.0

Change-Id: I88e630fcfcffd8a795f1abbeecd71a258d0e8e81

SystemUI: recalculate clock position on removing empty shade views

Change-Id: I70cc2dd3e1da99d4467cd43fc81018ccf135cd77
Signed-off-by: Roman Birg <roman@cyngn.com>
(cherry picked from commit 4f965c58)

SystemUI: fix clock jumping when expanding QS from lockscreen

commit 4f965c58 fixed recalculating clock position from shade_locked but
it didn't account for other scenarios such as when the QS is expanding,
causing the clock to jump when expanding QS from lockscreen.

Change-Id: I0e4f473fbc500f7dcdfa015cbedda07761c3cdb2
Signed-off-by: Roman Birg <roman@cyngn.com>
(cherry picked from commit 6831615a)

SystemUI : Fix left/center clock visibility

Change-Id: I5bee0927ceaf93ea4cc0751bcb866aaaed64356b

SystemUI : Make clock/navigation multi-user compatible

Change-Id: Ie6a1552aeb31e138221143d548f7cd4cbb5bde7e